Atmor AT91027TP, AT91018TP, AT91024TP User Manual

Electric Tankless Water Heaters

ThermoPro Series

18kW, 24kW, 27kW

www.atmorusa.com

Important Safety Guidelines

DANGER: Indicates an imminently hazardous situation which, if not avoided, will result

WARNING: Indicates a potentially hazardous situation which, if not avoided, could

CAUTION: Indicates a potentially hazardous situation which, if not avoided, may result

(Used without word) Indicates a safety related message.

SAVE THIS INSTRUCTION MANUAL FOR FUTURE REFERENCE.

Definitions: Safety Alert Symbols and Words

This instruction manual uses the following safety alert symbols and words to alert you to
hazardous situations and your risk of personal injury or property damage.

in death or serious injury.

result in death or serious injury.

in death or serious injury.

NOTICE: Indicates a practice not related to personal injury which, if not avoided, may
result in property damage.

WARNING: READ THIS INSTRUCTION MANUAL THOROUGHLY AND COMPLETELY
BEFORE INSTALLATION AND USE. FAILURE TO DO SO COULD CAUSE DAMAGE TO
PROPERTY, SERIOUS INJURY OR DEATH, AND VOID YOUR WARRANTY

Contact service directly if you have any questions regarding your unit.

Monday – Friday, 9AM–5PM EST

Phone: [phone]

Email: [e-mail]

WARNING: Cancer and Reproductive Harm –
www.P65Warnings.ca.gov.

AVERTISSEMENT: Cancer et Troubles de l'appareil
reproducteur – www.P65Warnings.ca.gov.

ADVERTENCIA: Cáncer y Daño Reproductivo –
www.P65Warnings.ca.gov.

For California residents / Pour les résidents de la Californie / Para residentes en California

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Table of Contents

1. Safety Guidelines ------------------------------------------------------------------------------------------ 4

2. About Your Atmor Electric Tankless Water Heater ----------------------------------------------- 4

3. Selecting an Installation Location --------------------------------------------------------------------- 5

4. Mounting the Water Heater ----------------------------------------------------------------------------- 6

5. Plumbing Requirements and Precautions ----------------------------------------------------------- 7

6. Plumbing Installation -------------------------------------------------------------------------------------- 8

7. Electrical Requirements and Precautions ----------------------------------------------------------- 9

8. Electrical Installation ------------------------------------------------------------------------------------ 10

9. Flow Rate -------------------------------------------------------------------------------------------------- 12

10. Operation Guide------------------------------------------------------------------------------------------ 12

11. Care and Maintenance --------------------------------------------------------------------------------- 13

12. User Interface/Controls --------------------------------------------------------------------------------- 14

13. Troubleshooting ------------------------------------------------------------------------------------------ 16

14. Reset Unit -------------------------------------------------------------------------------------------------- 18

Before Installing

By installing this product, you acknowledge the terms of the manufacturer’s warranty and
authorized dealer’s return policy. Once the heater is installed, do not return the product to
the place of purchase. If you have any questions regarding the warranty or the product return
policies, contact Atmor by phone or email.

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1. Safety Guidelines

Read this manual thoroughly before installing and using the instant water heater. Failure to
comply with the safety, installation or operating instructions will void the product warranty.
The product manufacturer and the product distributor will not be liable for any damages or
injury caused by failure to comply with the installation and operating instructions specified in
this manual or by improper use of the product. For best performance, ensure that this water
heater is installed in accordance with all electrical and plumbing codes applicable to your
area, and as specified in this guide.

This product has more than one power supply connection point. Do not attempt to install,
clean, inspect, disassemble, service or repair the water heater without first shutting off all the
power to the unit by means of the circuit breakers on the main electrical panel.

WARNING: Failure to adhere to the safety guidelines might result in severe injury or
death. The water heater must be installed in compliance with all national, state,
provincial and local electrical and building regulations. We recommend that you consult
a qualified electrician and a qualified plumber in case you have questions about
anything relating to codes for this product.

This product is intended for household and indoor use only. Do not immerse in water.

Each breaker used to power this unit must be grounded by means of the electrical
panel.

The heater must be connected directly to dedicated circuit breakers on the main
electrical panel.

Do not install the heater where it may be subjected to direct sunlight, rain, splashing
water, moisture/humidity or freezing temperatures.

This unit is intended for heating water only. Do not attempt to use the unit for heating
any other kind of liquid.

2. About Your Atmor Electric Tankless Water Heater

Congratulations on your decision to purchase one of the finest instant water heaters
currently available in the market! Your new instant water heater has advanced water flow
rate and temperature sensors that are designed to modulate power to the heating elements
to maintain a user-selected output water temperature range for 18kW/ 24kW/ 27kW: 86°F
(30°C) to 122°F (50°C) (subject to the temperature of the incoming water).

WARNING: When setting the water temperature of the instant water heater, be sure to
consider safety and energy conservation. Prolonged skin exposure to water temperatures
above 120°F (49°C) can result in severe burns or death. The maximum temperature setting
on this instant water heater is 122°F (50°C). Always take precaution to feel the water before
bathing or showering, and make sure the temperatures are not too hot. You are required to
read and comply with the following Time/Temperature Relationship chart to determine the
right water temperature for your home.

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Temperature

Exposure Time Resulting in Scalding

120°F (49°C) 5 minutes of exposure

122°F (50°C)

3 minutes of exposure

ThermoPro 18

13-3/8 x 17-3/8 x 5-1/4

17

3/4"

If you have small children, disabled, or elderly persons in
your home, you may require a setting of 120°F (49°C) or
lower to ensure their safety. Water temperature is
regulated by the knob on the front of the water heater

3. Selecting an Installation Location

• This water heater is designed for indoor installation only.

• The heater should not be installed in a location where it might

be subjected to freezing temperatures, since frozen water in
the unit can cause severe and irreversible damage which is
not covered under your warranty.

• The water heater should be placed in a location that is easy

to access.

• Ensure that the water heater, as well as the power

• Children, disabled and

elderly are at high risk
of being scalded.

• See instruction manual
before setting your
desired hot water
temperature.

• Always feel water

before bathing or
showering.

supplies and water connections, are out of the reach of children to prevent them
tampering with controls or touching an extremely hot pipe.

• Do not install the unit where it is may be exposed to excessive humidity, moisture or

dust, or where it may be splashed with water or other liquids.

• Do not install the unit below water pipes or air conditioning lines, where it is susceptible

to leaking or dripping water or other liquids.

• Do not install the unit above electrical boxes or junctions.

• If possible, avoid installation in a location that could be damaged due to leakage from the

water heater. Install a drip pan with drainage, or an active leak detector and automatic
shutoff valve, to prevent damage in case of a leak.

Item # Unit dimensions (inches) Weight (lbs) Connections

ThermoPro 24 13-3/8 x 17-3/8 x 5-1/4 17 3/4"
ThermoPro 27 13-3/8 x 17-3/8 x 5-1/4 17 3/4"

WARNING: Water heater are heat-producing appliances. To avoid damage, injury or
death, the water heater must be installed in a manner that prevents contact with any
substances or materials, and proper care must be taken to prevent unnecessary
contact (especially by children) with the water heater. UNDER NO CIRCUMSTANCES
SHOULD FLAMMABLE MATERIALS, SUCH AS GASOLINE OR PAINT THINNER,
BE USED OR STORED IN THE VICINITY OF THIS WATER HEATER OR ANY
LOCATION FROM WHICH FUMES COULD REACH THE WATER HEATER.

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4. Mounting the Water Heater

1. The instant water heater must be secured to solid mounting surface with four screws

(minimum 1” (25.4mm) long).

2. Make sure the unit is level before fastening the screws.

3. The unit must be installed in an upright position with the water inlet and outlet at the
bottom of the unit. Do not install with connections on top or the sides.

4. Do not install the unit above electrical boxes or junctions.

5. The water heater must be installed in a manner that prevents contact with flammable
materials. Keep flammable material at least two feet away from the heater and the hot
water outlet pipe. The water heater and the hot water outlet pipe must be secured, and
out of children’s reach to prevent tampering with controls or contact with an extremely
hot pipe.

6. If installing the heater on an upper floor or attic, make sure installation complies with the
local codes. Install a drip pan with drainage, or a leak detector and automatic shutoff
valve, to prevent damage in case of any leakage.

7. Unscrew the 4 cover screws, and remove the unit cover. (Figure 1)

8. Disconnect the cables from the PCB within the unit. (Figure 2)

9. Use 4 mounting screws that are at least 1 inch (25.4mm) in length, mount the unit on the
wall. (Figure 3)

10. Make sure the unit is leveled horizontally, with water inlet and outlet at the bottom.
(Figure 4)

Figure 1

Do not install upside down or on its side.

Figure 2

Figure 3

Figure 4

Figure 5

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